Linux Kernel RCU Vulnerability in IRQ Handling by Vendor

CVE-2025-39744

What is CVE-2025-39744?

A vulnerability has been identified in the Linux kernel related to improper handling of IRQ during the execution of rcu_read_unlock_special(). This issue can lead to a deadlock scenario when an IPI (Inter-Processor Interrupt) is issued during irq_exit(), resulting in a recursive lockup. Specifically, this vulnerability impacts the kernel's ability to manage the irq_work state correctly, especially evident when certain BPF programs are activated on tracepoints such as trace_tick_stop(). A fix has been applied to prevent this lockup by managing the IRQ work state effectively, ensuring a stable and reliable kernel performance.

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